System of space signaling.



1. c. ARMOR. SYSTEM OF SPACE SIGNALING.

APPLICATION FILED IULYZB. I912. I 1,219,215. I I Patented Mar.13,l917.

v2 SHEETS-SHEET 2- H I EI- m 3 /BY A 7 ATTORNEY JAMES c. Anmon,

OF BROOKLYN, NEW YORK, ASSIGNOB '..0 GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

SYSTEM OF SPACE. SIGNALING.

Application filed July 26, 1912. Serial No. 711,1120.

To all whom it may concern:

Be it known that I, JAMES C. Amuoe, a citizen of the United States, and a resident of Brooklyn, in the county-of Kings and State of New York, have invented a new and useful Improvement in Systems of Space Signaling, of which thefollowing is a specification. I

My invention relates to systems of space signaling and it has particular reference to the transmitting station of a system of wireless' telephony. I

()ne of the objects of my invention is to provide a system of the above-indicated character which shall be simple in arrangement, effective, efficient and powerful inoperation and shall embody means for eflectin. variations in the frequency or the amplltude, or both, of the electromagnetic waves that are radiated into space from the antenna, in response'to acoustic vibrations produced by sound or, in particular, by articulate speech.

Another object of my invention is to embody,.in a system such as just referred to, inductive means, the inductance of which may be varied in accordance with sound waves produced by speech.

Another object of my invention is to provide means whereby the inductance of suitable inductive devices may be rendered dependent upon the current of an auxiliary circuit which includes a transmitting device similar to the well-known microphone-transmitter, or other suitable device for effecting changes in resistance of an electric circuit in response to vibrations produced by speech.

A still further object of my invention is to provide adequate electrical means where by the normal inductance of the inductive means "referred to, may be maintained at approximately a predetermined value.

In the prior art, it has been customary,

in systems of wireless telephony, to employ.

a transmitting device directly in the antenna or the oscillation circuit, whereby variations in the amplitude or intensity of the high-frequency oscillations are effected directly by reason of the varying resistance of the transmitter, as will be readily understood. a

According to my invention, I propose to I vary either the frequency or the amplitude,

or both, of the electrical oscillations and,

Specification of Letters Patent. I

Paar-aid Mar. 13, 1917.

in so doing, I enpl y d inagnetizable core which is associatt or inked with the highfrequency sending circuit and which is provided with a plurality of windings which are supplied witl'. energy from an auxiliary directcurrent source. One of the windings is included 'in circuit with a reversing switch, an inductance and a variable'resistancewhereby the magnetizing current may be ad usted in order to maintain the core at any particular flux density or degree I of saturation, and the other winding is connected' in circuit with a transmitting device by'means of which the current may be variedjn response to speech, whereby variatio'rfs in the induztance of the magnetizable core are effected. In this way, the frequency orthe amplitude, or both depend ing upon the loc ation'of my inductive device as hereinafter pointed out, of the electrical oscillations and, therefore, of the electromagnetic waves radiated into space,

is varied in accordance with well-known principles and the signals transmitted are v rendered respons .ve to the sounds or speech. which alfect the uransmitting device.

In one of its aspects my invention may be considered as err bodyi-ng-a method of and;

means for amplifying variable currents in the sense that the variations of the current flowing in the contro ling circuit are reproducedin muca greater'amplitude by the current which is controlled even though the N 'controlled jcurre1 it may be of an entirely difl'erentform from the controlling current.

It is well known that if a current of constant value be su pplied to an oscillation circuit and the frequency thereof be gradually increased,the current in the antenna circuit increases to 1 maximum and then gradually decreases. If these values be plotted, a peaked curve is obtained, the peak occurring when the frequency is thatfor which the antenna circuit is tuned and the slope thereof dependir g upon-the electrical char aeteristics of the antenna circuit. Inasmuch as theeiiergy ra iiated from the antenna is a function of the antenna current, it is evident that the intensity or amplitude of the radiated wavesmay be varied according to the variations in frequency which may be effected by speecii through the agency of my mal inductance of my inductive device at such a value that the antenna and the oscillation circuitshall not have exactly the same natural period and to work entirely-on onecorresponding increases in the antenna current and, hence, in the intensity or amplitude of the energy radiated, and vice versa. Moreover, I propose to work at substantially the steepest portion of the curve where -a very considerable change in the radiated energy may be effected by an extremely slight variation in the frequency, it being understood that the radiated energy varies as the square of the antenna current.

Itshould be understood that, with my inductive device in the oscillation circuit and a loose coupling between the oscillation circuit and the antenna circuit, the antenna will always oscillate at its own natural fre quency, regardless of changes of frequency in the oscillation circuit and, hence, variations in the intensity or amplitude only of the waves radiated will be effected. If the device is connected in the antenna circuit, however, the frequency also of the waves radiated into space will be changed in response to speech. I

In case a close coupling is employed, variations in the frequency of the radiated waves are effected with the inductive device in either the oscillation or the antenna cir- 7 illustrates my preferred form of inductive,

device connected as an auto-transformer in the antenna and oscillation circuits; Fig. 8.

is av view similar to Fig. 2 showing inductive means of a similar form to that shown in cuit. Perhaps the best arrangement is toemploy a loose coupling and connect the inductive device in the antenna circuit, whereby changes of both the amplitude andthe frequency of the radiated waves are effected, thereby strengthening or enhancing the effeet on the receiving station which, of

. course, must be sharply and selectively tuned.

It should be understood that in using the term non-inductive relation in connection with the high frequency and the direct current windings, I mean that the flux produced' by the one does not pass through or link the other and, hence, does not inducea voltage therein, in accordance with well known principles. The inductance of the high frequency circuit, however, may be varied by changes in the direct current, inasmuch as such changes affect the magnetization or saturation of the core.

My invention may best be understood by reference to the accompanying drawings, in which Figure 1 is a diagrammatic view of a transmitting system embodying my invention; Fig. 2 is a diagrammatic view similar to Fig. 1, illustrating a modified form of my inductive means5Figs. 3 and 4 arealso diagrammatic views showing further modifica- Fig. 1 and connected as a coupling link be: tween the antenna and the oscillation circuit; Fig. 9 is a diagrammatic view of a typical transmitting system showing various locations of my inductive means by a conventional symbol for variable inductance,

and Fig. 10 is also a diagrammatic view of.

another typical arrangement of circuits of a transmitting system in which the various locations of my inductive means are indicated in the same manner as in Fig. 9.

Referring to Fig. 1, a generator 1 adapted to generate alternating current of from .thirty thousand to two hundred thousand oscillations per second delivers energy to an oscillation circuit 2 which includes an adjustable inductance 3, a condenser 4 and a primary winding 5 of a transforming device 6. A secondary winding 7 of the transforming device 6 is connected in an antenna circuit 8 between an antenna 9 and the ground G and in circuit with an adjustable inductance 10 and my variable inductive means 11. The generator 1 is merely illustrative of any suitable source of high-frequency oscillations, and, bysuitably arranging. the devices and circuit connections of the oscillation circuit, any other suitable source of energy may be employed, su'chas the well known Poulsen arc. Moreover, I do not wish to be restricted to the specific arrangements, circuit connections and relationships of the source of energy, the oscillation and the antenna circuits, as, broadly considered,

I contemplate employing any of the wellknown arrangements of circuits in this art.

The antenna circuit 8 is divided at points 12 and 13 into a plurality of branch circuits 14 and 15 which are surrounded, respectively, by means of suitable tubes 16 of insulating material, such as mica or other material of high dielectric strength. Each of the tubes 16 is surrounded or linked by a plurality of magnetizable cores 18, preferably in the form of rings and which are preferably composed of a plurality of small wires or thin laminations in order to'prevent excessive heating. Each of the cores 18 is provided with a plurality of windings 19 and 20 and the several windings 19 are connected in opposition across the terminals of an auxiliary battery 21 and in circuit with a transmitting device 22 which may con- 23egispihpi 1 eme ic t s wi e a e no rent-in the transmitterecircuit. 'curr nt; inthe Wiiiding is 'tained sub'stantially constant v "ur'n'ingf thecircu tcpnnections to be as and ithe" high f equeiicy generator 1, H her suitiible sourc of energ g t be pro-' (lacing electrical os'cil tions ofjthe deslred frequency in' th' pjsqillation circhit 2, the oiie'lfation he 's'ystein' -is as follows; I l The iieversi'hg Switch-211s first closed upon ripper ccntact terminals inorder to com filete" a' circuit throil'gh "the windings; 20 (if t v rhl cores H18;Jdft"e r hieh: therenc'e =-23-isx adjusted until the: cul'ilint hich. sh ll Y e b's' cillatlcn circuit In me casesg the totaleinductahce ma be included in my variable inductive means, while,- u'hd'r' othercircuiri'smn it may 1 be necessar to-empl oy the auxilimyadjustehle iiidec t-ance 10. In eitherca he antenna circuit is tuned to a ipr'oxirha y. resonance di t ione and th inductance t "reef mainubsmhtiany ed-fists t,' theft the s-ys:

11 workuhder t-Iie mtis't advantageous ltlons',fwherebyefiective and reliable ope iomniay be secqred.; P 3 x If -the current traversing the windings 19 i'sl vii ed by-r eans of the tra emitter 22 in res n'se'; to ,sourids'cr"speech,*,m ac ordhhc withi wdl-k" owh pr'ac'ticefi'tl is -Videi1t that the H vree-hi s'aturationof the cereals and, thererore; the inductance in thejiantehna air cui tis-varied above and below thepredeter-r mined t'alu'for which the antenna circuit is t'uhed By nieansofthese va'jriations in indiictance-in response to speech, the fre quehe and amplitude bf the oscillations rhdiii iteg from the antenna are accordingly 60' Infi'smuch as the branch circuits 14 and 15 of' the antenna circuit forl'n a closed loop, it is evident that there will be'slig'ht circulating currents produced by reason of the changes of flux in the cores 18, but these cir 5 culating currents will be very small andwill able '1 bf con iruction a rd isgadapted to disch for the purpose of clarness, i-t being'beyPl ange ensei' 4 periodically, wherebya 1se= cone the and fies ofvery high-frequency oscillations ere 15;;

prodiiced in the o; ;cillati0n circuit 5 5 The particular means whereby 't' highfrequency oscillations are prodiiced' no part of my in venti onfex cepta forms a useful fuilction' ing th'eop ration of 5;; the system, and :11 [y suitable'nleans" fer pro- 3 ducing the sarne re sults'nhjiy be enipleyed.

The variable in luctiye means 11: which connected in the uitenna circuit 8; betweenthe antenna 9'and the oscillation cii'cuit 2 is M of the same genei ail fortn as 'that' de ribed g with respect to Rig.- 1, but di fers therefrom in that thebranch line's 14 and 15- ai'e sever: y prov ded-a zp i fiyer loops es which as re threaded through the .connectedin the s2 me manner as set Fig. 1. The'latterconnectionsare omitted lieved that those skilled in-thefart will readily understand the circuit connections thereof.- I a The arrange "entof circuits, forth in Fig flinay be foul 1d desirable under certain of thesystem is s rnilar 'tdzthat already described inydejthi l no further des ription thereofis deemed necessary; Obvioiisfly, cirit 'culating currentswill alsd be established in thelogp c0mprisi:1g the branch circuits 14 and1-..

g In Fig. 3 a-po'rt ion 29 o fr the antenna cir- 4 they are which are connected in the manner hereinbefore set forth. Since there are no closed loops of' the antenna circuit in the circuits shown in Figs 3 and 4, no circulating currentsare produced.

Referring now to Fi 5, a transmitting system embodying similar devices and circuit connections to those shown in Fi 1, is provided with a modified form of in uctive device 34 which constitutes the preferred embodiment thereof. The inductive device 34 comprises a magnetizable core 35- which is preferably composed of a plurality of insulated laminations or punchings (not shown) which are provided with a plurality of openings or apertures 36 that are disposed in pairs atright angles, the one to the other. The antenna circuit8 is threaded through one pair of apertures 36 in a plurality of turns 28, while two direct currentwindings 19 and20 are disposed in the other set of apertures-which are at right angles thereto.

Inasmuch as the antenna winding 8 and the direct current windings 19 and 20 are disposed at right angles, it is evident that non-inductively related in the sense already defined and, hence, there will be no tendency for alternating high frequency oscillations to be impressed upon thefdirect current windings.

The winding 19 is connected across the terminals of the battery 21 and in circuit with the transmitter 22, 20 is connected across the battery 21 and-1n circuit with the reversing switch 24, the inductance 23 and the adjustable resistance 23.

The operation of this system is substantially like that already described, it being understood that the normal inductance of the inductive device 34 is maintained at approximately a predetermined value by means of the direct current winding 2-0, and variations above and below this normal value are effected in accordance with sound waves produced by speech through the agency of the winding 19 and the transmitting device 22. Hence, the frequency and the amplitude of the oscillations and, therefore, of the electromagnetic waves radiated from the antenna, are accordingly varied.

In F'g. 6, a transmitting system similar to that shown in Fig. 2 is set forth, in which the preferred form of my inductive device 34 is linked through both the oscillation circuit 2 and the antenna circuit 8 and thus serves as a transforming device ora coupling link bet een said circuits. cillation' circuit 2 and the antenna 8 are insulated, one from the other, inductively related, being threaded through one pair of apertures 36 of the inductive device 34. Direct-current windings 19 and while the winding and are 20 are also providedvand are dis osed in the other set of apertures 36 whic are located substantially at right angles to the set just referred to..

In Fig. 7 my inductive device 34 is associated with the oscillation circuit 2 and the antenna circuit 8, being connected as an auto-transformer, which serves as a couplmg link between the circuits mentioned. The conductor 37 which forms a common circuit for both the oscillation circuit 2 and the antenna circuit 8 is rovided with a plurality of turns 28 which are disposed in one set of apertures 36.

Direct-current windings 19 and 20 are also provided and are located in the remaining set of apertures 36 and are thus nonin'ductively related to the alternating current circuit 37 The auxiliary connections of the direct current windings 19 and 20 in both Figs. 6 and 7 have been omitted for the reason that these connections have been fully described and it is deemed unnecessary to set forth the same in detail again.

It will be understood that as the currents in the direct-current windings 19 and 20 are varied, either by adjustment or by small increments in response to speech, that variationsin the mutual inductance of the oscillation and the antenna circuits are ef-.

fected, whereby in amplitude accomplished.

Fig. 8 shows a system similar in its main circuit connections to thatshown in Fig. 6 and, in place of the preferred-form of my inductive device 34, I have illustrated the form shown in Fig. 1 which is so con nected as to serve as a coupling link bechanges in frequency and tween the oscillation circuit 2 and the antenna circuit 8.

Not only are the conductors l t and 15 of the antenna circuit threaded through the several insulating tubes 16, but a plurality ofbranch lines 38 and 39 of the oscillation circuit 2 are also disposed within said insulating tubes and, inasmuch as said tubes are surrounded by inductive cores 18, in the of the oscillations may be manner hereinbefore set forth, it is evident that the antenna and the oscillation circuits are inductively related and that the induc-v tive means 11 serves as a between them. 4

In general, the operation of this system is similar to that already set forth and further description thereof is deemed unnecescoupling link sa-ry.

In Fig. 9,1 have shown a typical arrangement of circuits of a transmitting system such as is frequen'ly employed in the art,

and I have illustrated symbolically my inductive means connected in various locations at, b, c, d and e which said means may results, allbut one of such inductive means not attempted to show the circuit connecbeing indicated by broken lines.

When inserted in the system at a or b,

theinductive means is connected in the oscillation circuit 2, when connected at c it is included in both the oscillation circuit 2 and the antenna circuit 8, While if located at (l or c, it forms a part of' the antenna circuit only.

In Fig. 10, another typical arrangement of circuits such as are frequently employed is illustrated, in which a specially tuned circuit 40 is employed between the oscillation circuit 2 and the antenna circuit 8,

for the purpose of transferring energy between them. Here again I have illustrated symbolically various locations f, g, h, 2' and j in which my inductive means may be connected, all but one of such means being indicated by broken lines.- If included in the circuit at f, the inductive means forms a part of the oscillation circuit 2; if at g, it constitutes a part of the specially tuned circuit 40, and if at h, it constitutes an element in the antenna circuit 8. My device may also be included at a or j, in which cases it serves as a coupling link between the several adjacent circuits.

In connection with Figs. 9 and 10, I have tions of my inductive means, nor shall I attempt to describe the operation, for the reason that these details have been fully set forth hereinbefore' and thoseskilled in the art will readily understand the various circuit connections that may be employed and the operation of the systems.

Although I have shown and described my invention as embodied'in several different. arrangements and locations of devices and circuits, my inventionis not confined alone to the particular arrangements set forth and many modifications may be effected therein without departing from the spirit and scope of my invention.

I claim as my invention: v 1. The method which consists 1n producing a magnetlzing field by means of a variable electric current, producing a high frequency. alternating current and subjecting the high frequency alternating current to the action of. said magnetizing field in such a manner that the variable current circuit will be unaffected by the highfrequency alternating current.

2. Themethod which consists subjecting twomagnetic circuits to the action of a pulsating current, producing a high frequency alternating current, and conducting said high frequency alternating current within the influence of s'aid'magnetic circuits. in such a anner that the magnetizing effects of the alternating current upon the alternating current, :mdsubjecting said high frequency alternating current to the action that the electromoti e forces induced in the circuit of said variible electric current by the high frequency alternating current are substantially equal and opposite, simultaneously producing by It constant direct current two other magnetizing fields and superimposing said last nentioned magnetizing fields upon the first mentioned magnetizing fields. a

4. The method of amplifying a pulsating unidirectional curre it which consists in producing a magnetizir g field b means of said current, producing a high requency alternating current, and subjecting said high frequency alternating current to the action of said magnetizing field in such a manner that the pulsating unidirectional current circuit will be unaffected by the high frequency alternating current.

5. The method of amplifying a varying electric current which consists in producing by said varying elactric current two magnetizing fields, producing a high frequency frequency alternating current to the action of said magnetizing; fields in such a manner that the magnetizir g eflects of the alternating current upon ihe varying electric current circrit are opposite.

6. The method cf amplifying a variable electric current wh .ch consists in producing ducing said magnetizing fields Will-.b unaffected by the high frequency alternating current.

7. The method cf controlling the flow in an electric circuit (-f a. high frequency alternating current whch consists in producing of said magnetizing fields in such a manner alternating current, and subjecting said high a by a controlling electric current two magnetizing fields and subjecting the high frequency alternating; current flowing in the circuit to the action of said magnetizing fields in such a manner that the magnetizing effects of the alter nating current upon the controlling curren". circuit arel opposite.

8. The method of controlling the flow in an electric circuit of a high frequency alternating current which consists in producing by a varying electric current two magnetiz mg fields and subjecting the high frequency alternating current flowing in the circuit to the action of said magnetizing fields in such a manner that the electromotive forces induced in the circuit of said varying electric current by the high frequency alternating current are substantially equal and opposite.

9. The method ofcontrolling the flow in an electric circuit of a high frequency alternating current which consists in producing by a controlling electric current two magnetizing fields, subjecting the high frequency alternating current flowing in the circuit to the action of said magnetizing fields in such a manner that the magnetizing effects of the alternating current upon the two magnetiz-' ing fields are opposite, simultaneously producing by a constant direct current two other magnetizing fields, and superimposing vsaid last mentioned magnetizing fields upon thefirst mentioned magnetizing fields. I

10. An' apparatus of the character described, comprising two magnetic cores, a

' winding on each of said cores arranged to carry a pulsating unidirectional electric current, and a second winding linked with each of said cores and arranged to carry an alternating current of a frequency higher than the pulsations of said unidirectional current, the corresponding windings of each core being connected in series and so that the electromotive forces induced in the unidirectional current carrying windings by the action of the alternating current are substantially equal and opposite.

11. An apparatus of the character described comprisingtwo magnetic cores, a Winding on each of said cores for carrying a pulsating unidirectional current, a second winding linked with each of said cores for carrying a high frequency alternating current, the windings being so related to each other that the circuit supplying the pulsating current will be unaffected by the high frequency alternating current, and a third winding on each of said cores for imparting an initial constant megnetization;

12. An! apparatus of the character described, comprising two magnetlc cores, :1

' ,coil wound on each of said cores for carrying a pulsating unidirectional electric current and a second coil wound on each of said cores arranged to carry an alternating current of a frequency higher than the pulsations of said unidirectional current, the corwinding on each of said cores for carrying responding coils of each core being connected in series and so that the magnetizing relation of the coils of one core is opposite to the magnetizing relation of the coils of the other core.

13. An apparatus of the character described, comprising two magnetic cores, a

a controlling electric current, a second winding linked with each of said cores for carrying a high frequency alternating current, the windings being so related to each other as to prevent high frequency current from flowing in the circuit supplying the control. llng current and a third winding on each of said cores for imparting an initial magnetization.

14:. An apparatus of the character described, comprising two magnetic cores, a winding on each of said cores for carrying a controlling electric current, a second winding linked with each of said cores for carrying an alternating current, the corresponding windings of each core being connected in series and so that the magnetizing relation of the windings of one core isopposite to the magnetizing relation of the windings of the other core, and a third winding'on each of said cores for imparting to said cores an initial magnetization.

15. Means for controlling the flow of high frequency alternating current in an electric circuit comprising two magnetic cores, a winding for each of said cores supplied by a controlling electric current, a second winding on each of said cores supplied by a constant direct current, and means for subjecting the alternating current to the action of the magnetic field produced by said windings in such a way that the electromotive force induced in each of said windings by the alternating current are substantially equal and opposite.

16. Means for controlling the flow in an 1 electric circuit of a high frequency alternating current comprising a magnetizing field produced by a controlling current, a second magnetizing field cooperating with the first and produced by a constant direct current and means for subjecting the hi h frequency alternating current to the actlon of these fields in such a manner that the circuits pro-;

ducing said magnetizing fields will be unaffected by the high frequency alternating current.

17. Means for controlling the flow in an electric circuit of a high frequency alternating current comprising a ma etizing field produced by a pulsating unidirectional current, a second magnetizing field cooperating with the first and produced by a constant direct current and means for subjecting the high frequency alternating current to the action of these fields in such a manner as to prevent high frequency alternating currents from flowing in the circuits producing said fields.

18. Means for amplifying a variable electric current comprising a magnetizing field produced by the variable current, a circuit supplied by a source of high frequency alternating current and means for subjecting said high frequency alternating current to the action of said magnetizing field in such l be unafi t d 3 high i equegey l t ng urrent- 19. An apparatu for amplifym a Pub Sating un d r c on 'e ehifc 'w'rrent, ri ng a Source of highfreq eenoy hilt? m ting c r nt, a cir ui 1 p i d by aid source, two eactances iiicl'u ed in Said cipcu t, nd t o m gn t ing 9011s adapted to carry the Current to be an} lified and inducw y te'df aid ra'iteneel ins h a nne thatv the 'e ect bmq i e f r e n,- diwed in th t o mam tilin c s b th ac n of the lternatmg 'urrent' re i bstantiay qual nd mi 0 n? 20. Means fbr ampfiyirig a va 'iable (fle tri c current comprising a magnetizing field produced by the variable euirrent, a 'secb d magnetizing field cpiipera ting-kvihh the first and produced by =1 source "pf-epnstant direct Current, a circuit supplied by a source of high frequency alternating current and mearis for subjecting said high frequency alternating current to the action of Said ma e iz fi s n u h a mann tha the circuits prbducing Said magnel zizing fields will I t rna't g urr nt V QIQThe combinatio with a high frequency electrical circ uit Qf mggnetizgble members in i g said ir ui inegn i in i'indin'gs upp by q ltrqll 'n 11mm as soeih ted with said members and so related 'the altern t n r n; i'rciuit as to, Iii-eient high frequency electrical clihre ts fl'ow tig in h rc t' nly n 'th r 9 tr1 i mei h 22 Th mbinat Qn ith a hi h frequ ncy ele t c l r ui Of meg'e ti -hl be linafiehted-by the high 'f reqjuency allhe c mbieeiiee wiih 5% hi h, i

, 2,5 mega iz bl,

g c'uity m''gn izi' v h s -s.

c rrem a ec nd magnet z ng fi ld 906w- 2 j- The eom'b tipn w th an e c i al i ei it' s pli d by sour ojf hi h "ireqgeney alternating ei ti'ent, ofni'e'fll s for 69 p ing t flow 9f we iii leid i?- 'P!1Pri$i9 n !i i9? Prmlfi ng by c nstahftd te t' ur nt, a magne i i g fi d, mean f r p mlu y aont'relling curnt sr ol id'i i j n ti ii g' fi ld bo l' er g With't 'e first, i l-i n' I fQ H j t HQ h 'fylequegcy' al t-ing' current t fth ti 9f 'the ei ifild His'. 1 h a marin to pr" nt hi h frln n i' e neth bl fiQWing #he cir its re'du in e'id BUS. The cpq hination with a high frequency tric l c qit O m gneti 'bl members linking giirc'uithtivo' sets of a eetizing'w'ih n t id m n ti a'ble members, we Set- Of 'said windings beiiig sqp ph'ed by g ico s ta ijt direct current and thp tl'iei' set being supplied by a eoiitmlhhg current, the tivQ'sets f Windihgsbhing sp related to the 31h a 'natihg eurreiipcircuit as o plrei' nt hi h ll li'e' l yb ie l li nts Ir n mm; in the i c tsui p yiiig the ind lfl fi" 2 T embirn 71 1 w t n elec i ci e QPPhQ by eiirce e hi hf quenby eli ematihg current, of ian fer" c'on i n the fl of 91 w re i that f i uit .7 inhrs 1 2m d one set SH P Q, a e th be eelie em; elem Se.

of energy, an oscillation circuit associated' plurality therewith and an antenna circuit in cooperative relation with said oscillation circuit, of two magnetizable members associated with saidantenna circuit, a source of direct current, two sets of windings for each of said members, the windings of each set being connected inopposition and in series circuit with said direct current source and means for varying the current traversing one of said sets of windings.

31. In a wireless signaling system the com bination with a high frequency source of energy, an oscillation circuit associated therewith and an antenna circuit in cooperative relation with said oscillation circuit, of magnetizable members associated with said antenna circuit, a source of direct current, a plurality of windings for each of said members, one set of windings on said members being connected in opposition and in series circuit with said direct current source, and in multiple circuit with another set of said windings, and means for varying the current through one set of said windings.

32. In a wireless signaling system, the combination with a high frequency source therewith and an antenna circuit in coiiper ative relation with said oscillation circuit, of inductive means associated with said antenna circuit, two sets of windings for said inductive means, a direct current source of energy connected to said windings in. parallel, and means for varying the current supplied to one set of said windings.

33. In a. system of wireless telephony, the combination of an antenna circuit supplied by a source of high frequency energy, inductive means associated with said antenna circuit, two sets of windings for said inductive means, a .direct current source of energy connected to said windings in parallel, and a transmitter in circuit with one set of said windings.

3i. In a system of wireless telephony, the combination of an antenna circuit supplied by a source of high frequency energy, inductive means associated with said antenna circuit, a source of direct current, a plurality of windings for said inductive means connected in opposition and adapted to be energized by said source of direct current, and means for varying the current traversing said windings in response to speech.

35. 'In a system of wireless telephony, the combination with a high frequency source of energy, an oscillation circuit associated therewith and an antenna. circuit in cooperative relation with said oscillation circuit of inductive means associated with said antenna circuit, a source of direct current, a of windings for said inductive means connected in opposition and adapted to be energized by said source of direct .cur-

36. In a system of wireless telephony, the

combination with a high-frequency source of energy, an oscillation circuit associated therewith and an antenna circuit in cooperative relation with said. oscillation circuit, of inductive means associated with one of said circuits, two sets of windings for said inductive means, a direct current source of energy connected to said windings in par allel, and a transmitter in circuit with one set of said windings.

37. In a system of wireless telephony, the combination with a high-frequency source of energy, an oscillation circuit associated therewith and an antenna circuit in cooperative relation with said oscillation circuit, of a magnetizable member associated with one of said circuits, two sets of windings there for, a source of direct-current connected to said windings, and a means for varying the current supplied to one set of said windings in response to speech.

38. In a system of wireless telephony, the combination with a high frequency source of energy, an oscillation circuit associated therewith and an antenna circuit in cooperative relation with said oscillation circuit,

of a magnetizable member associated with said antenna circuit, two sets of windings therefor, a source of direct current connected to said windings and a telephone transmitter in circuit with one set of said windings.

39. In a system of wireless telephony, the combination with a high-frequency source of energy, an oscillation circuit associated therewith and an antenna circuit in cooperative relation with said oscillation circuit, of magnetizable members associated .with one of said circuits, a source of direct current, a plurality of windings for said mem- "bers adapted to be energized by said direct tion, and a telephone transmitter in circuit with said windings.

41. In a system of wireless telephony-,1 the..-

combination with a high-frequency source of energy, an oscillation circuit associated therewith andan antennav circuit in coiiperat ve relation withwsa d oscrllationrcircuit;

related windin of magnetizable members associated with one of said circuits, a source of direct current energy, a plurality of windings for each of said members, one set of Said windings on said members being connected in opposition and in series circuit with said direct current source and in multiple circuit with another set of said windings, and means for varying the current traversing one of said sets of windings in response to speech.

a -42. In a system of wireless telephony, the

combination with a source of high-fre quency alternating current energy, an oscillation circuit and an antenna circuit, of an inductive device serving as a coupling between said oscillation and said antenna circuits and having a plurality of inductively severally included in the aforesaid circuits, and means for maintaining a predetermined inductance of said device and for varying the inductance thereof in response to speech.

43. In a system of wireless telephony, the combination with a source of high-frequency alternating current energy, an oscillation circuit and an antenna circuit, of an inductive coupling between said oscillation and said antenna circuits, means embodying an auxiliary source of energy for maintaining a predetermined inductance of said coupling, and means embodying said auxiliary source and a transmitter for effecting changes in the inductance of said coupling.

H. In a wireless signaling system, the

combination with an inductive device, an oscillation circuit, an antenna circuit and an auxiliary circuit, all linking said device, of means responsve' to varying external conditions for changing the inductance of said device.

- .45. The combination in an apparatus of the character described of a transforming device having two magnetic circuits, a primary and a secondary winding for each magnetic circuit, a source of auxiliary magnetizing current adapted simultaneously to energize both magnetic circuits, a source of high frequency alternating current supplying said primary windings and means for varying the intensity of the auxiliary magnetizing current to correspondingly vary the amplitude of the high frequency current generated in the secondary windlngs 46 The combination in an apparatus of the character descrii ed of a transforming device having two magnetic circuits, a pri-' mary and a, secondary winding for each magnetic circuit, a scarce of auxiliary mag netizing current adaptedsimultaneously to energize both' magnetic circuits, a source of high frequency alter iating current supplying said primary winding,l a circuit containing the secondary winding, the inductance capacity and resistance of said circuit being suitably pi'oportioned to tune the circuit to approximate resonance with the current induced therein, and means for varying the auxiliary magnetizing current to vary the tuning of the secondary circuit.

47. The combinatim in an apparatus of the character described of a transforming device having two Iragnetic circuits, a primary and a secondary winding for each magnetic circuit, a source of auxiliary magnetizing current adapted to simultaneously energize both magnetic circuits, a source of high frequency altern ating current supplying said primary windings and signaling means connected with said auxiliary current source forvarying the intensity of the magnetic field in accordance with signals and correspondingly varying the amplitude of, the high frequency current induced in the secondary winding.

48. The combination in an a paratus of the class described :for a trans ormin'g device having two magnetic circuits, a primary and a secondary winding 'for each of July, 1912. a

JAMES C. ARMOR.

Witnesses:

T. THULER, O. E. Laasor. 

